For September 2023, the rare Blue Moon, is on August 30th; it is the second full moon in the month of August 2023. The moon lies to the lower left of Saturn, which reached opposition on August 26th. The waning gibbous moon sits just to the right of brighter Jupiter on September 5th. The last quarter moon is September 6th. The waning crescent moon lies to the upper left of bright Venus in the dawn on September 11th.

The new moon is on September 14, exactly a month before the annular eclipse in October. More on it next month! The first quarter moon is on September 22nd. The next day, fall begins with the Autumnal Equinox at 12:50 a.m. on September 26th. The waxing gibbous moon passes below Saturn in the SE dusk on September 26th. The Full Moon, the Harvest Moon, will be on September 29th.

Mercury lies too close to the Sun for visibility from Earth this month, but will emerge at dusk in October. But Venus is back, now west of the rising sun in the dawn, and dominating the morning skies. She is 28% sunlit and at her brightest on the morning of September 19th. Mars is lost on the far side of the Sun this month.

Jupiter reaches opposition in early November, and rises about 10 PM in the northeast in Taurus at midmonth. But Saturn is at its best this month, reaching opposition on August 26th, rising in the SE at sunset. It rings are now tilted about six degrees to our line of sight, and closing become edge on at its equinox in May 2025, almost invisible from earth for weeks. Note two of Saturn’s moons, Dione and Rhea, to the lower right.

To the northwest, we find the familiar Big Dipper getting lower each evening. Most know how to use the two pointers at the lower part of the bowl to find Polaris, our Pole Star, sitting about 30 degrees high all night in the northern sky.

From the Dipper’s handle, we "arc" SE to bright orange Arcturus, the brightest star of Spring, and still well up in the western twilight. Spike south to Spica, the hot blue star in Virgo. Note that Spica is now low in the SW, and by September’s end, will be lost in the Sun’s glare due to our annual revolution of the Sun making it appear to move one degree per day eastward. To the Greeks, Spica and Virgo were associated with Persephone, the daughter of Ceres, goddess of the harvest.

In their version of "Judge Judy", the beautiful young daughter falls for the gruff, dark god of the underworld, Pluto. He elopes with her, much to the disapproval of mother Ceres, and they marry in his underworld kingdom of Hades…a honeymoon in hell…really, he does love her as well, and the marriage itself works well. But it is the reaction of Ceres that creates alarm.

Very despondent over the loss of her young daughter to a fate as bad as death, Ceres abandons the crops, which wither. Soon famine sets in, and humanity appeals to Jupiter to save us all. Calling all together, Jupiter hears that Ceres wants the marriage annulled, Persephone loves them both, and Pluto wants his mother-in-law to stop meddling. Solomon style, Jupiter decides to split her up, not literally, but in terms of time. In the compromise (aren’t all marriages so?), when you can see Spica rising in the east in March, it means to plant your peas. For the next six months, she visits upstairs with as very happy mama, and the crops will prosper. But now, as Spica heads west (to the kingdom of death, in most ancient legends) for six months of conjugal bliss with Pluto, it is time to get your corn in the crib. This simple story, told in some form for as long as Noah’s flood, was one of the ways our ancestors 7,000 years ago knew the solar calendar and when to plant and harvest. As you watch Spica fade, thank this star for agriculture, and even our own civilization.

To the south, Antares marks the heart of Scorpius. It appears reddish (its Greek name means rival of Ares or Mars to the Romans) because it is half as hot as our yellow Sun; it is bright because it is a bloated red supergiant, big enough to swallow up our solar system all the way out to Saturn’s orbit! Near the tail of the Scorpion are two fine open clusters, faintly visible to the naked eye, and spectacular in binoculars. The clusters lie to the upper left of the bright double star that marks the stinger in the Scorpion’s tail.

The brighter, M-7, is also known as Ptolemy’s Cluster, since he included it in his star catalog about 200 AD. Here is the fainter but more beautiful Butterfly, M-6. (Note he appears to be fluttering down and to the left among the stars of the Milky Way here.)

East of the Scorpion’s tail is the teapot shape of Sagittarius, which marks the heart of our Milky Way galaxy. Looking like a cloud of steam coming out of the teapot’s spout is the fine Lagoon Nebula, M-8, easily visible with the naked eye.

The brightest star of the northern hemisphere, Vega dominates the NE sky. Binoculars reveal the small star just to the NE of Vega, epsilon Lyrae, as a nice double. Larger telescopes at 150X reveal each of this pair is another close double, hence its nickname, "The Double Double". This is fine sight under steady seeing conditions over 150X with scopes 4" or larger. Between the two bottom stars; the Ring Nebula, marked "M-57" on the Skymap, is a ring of gas and dust expelled by a dying red giant star while its core collapsed to a white dwarf. A similar fate is expected for our own sun in perhaps five billion more years.

To the northeast of Vega is Deneb, the brightest star of Cygnus the Swan. It was just NW of it that I discovered the brightest nova of my lifetime, Nova Cygni, on August 27, 1975. Here a shell of hydrogen around a white dwarf exploded suddenly, becoming a record (for a nova, at least) 20 million times brighter in a matter of hours. It went from not visible in any telescope to the sixth brightest star in the summer sky in less than a day, and I was looking at the right place and time to catch it still on the rise. But the total amount of expel gases was much less than in the Ring Nebula, and it faded below naked eye visibility in only two weeks. Fun while it lasted! Typically several nova outbursts are found every year in our Galaxy, and they do often recur, for neither star in the close binary system was destroyed, and the mass transfer can resume soon.

At the other end of the "northern Cross" that makes up the body of Cygnus is Albireo, the finest and most colorful double star in the sky. Its orange and blue members (I call them the "Gator Stars") are well resolved at 20X by any small scope. To the south is Altair, the brightest star of Aquila the Eagle, the third member of the three bright stars that make the Summer Triangle so obvious in the NE these clear September evenings. To the east, the Square of Pegasus rises. The long axis of the square points to the SE to Saturn in Aquarius. Jupiter will join the evening planet parade in October.